Abacus

Teak on teak inlay, rebar with rust patina

A wooden abaccus with a cube pattern inlayed on the side, placed on a blue surface against a dark background.
Close-up of wooden abaccus bead rows with two tones of wooden beads against a black background.
Close-up of a wooden chessboard with an intricate pattern of three-dimensional cubes, featured on a curved wooden surface.